An automatic player reenacts a music passage on an acoustic piano without any fingering of a human player; solenoid-operated key actuators and a solenoid-operated pedal actuator is provided for the keys and damper pedal; the automatic player makes the damper pedal travel along a simulative pedal trajectory, and the central processing unit stores pieces of control data expressing the pedal stroke together with the amount of mean current supplied to the solenoid-operated pedal actuator; the central processing unit analyzes the pieces of control data so as to determine an entry point of half pedal section and an exit point of the half pedal section, and specifies a target half point in the half pedal section; while reenacting a music passage, the automatic player brings the damper pedal to the half point so as to reproduce the half pedal state, exactly.